The present invention relates generally hair cutting devices wherein the cutting action is obtained by reciprocating blades such as clippers and trimmers. More specifically, the present invention relates to devices for adjusting the spacing between blades in hair cutting devices (collectively referred to as hair cutters) having a bladeset with a moving blade and a stationary blade.
In such bladesets, the moving blade laterally reciprocates relative to the stationary blade, and the moving and stationary blades are adjustable relative to one another in a direction normal to a direction of reciprocation. The distance between toothed ends of the blades is adjusted by releasing fasteners, which are typically screws, that connect the moving blade to a guide held by the stationary blade, and then adjusting the moving blade to the desired spacing. These screws must be sufficiently tightened so that they will not loosen when the clipper is in use.
For certain types of precision hair cutting and trimming operations, such as detail outlining, or cutting lines or patterns into a person's hair or the edge of the person's hairline, whether facial, scalp or body hair, it is desirable that the distance between the stationary blade and the cutting blade be small as possible. However, the teeth of the moving blade are preferably offset from the stationary blade to avoid cutting the skin of the person whose hair is being cut or trimmed. A balance between precision and skin damage is often the result of blade adjustment. Thus, it is desirable to adjust the moving blade so that it is offset from the stationary blade by a very small distance. Currently, such adjustments are performed by the naked eye, with the user (typically a hair professional) making difficult, precise adjustments to obtain the desired small gap between the toothed blade edges.
In the hair cutting industry, it is typical for manufacturers to set the bladeset spacing at the factory. Through normal use and maintenance, end users often are faced with the task of recalibrating the bladeset spacing. However, the end users were forced to perform such recalibration by eye. This method has obvious drawbacks due to lack of precision and consistency in the adjustment.
Accordingly, there is a need for a device that will facilitate consistent adjustment of blades by end users, among others, to extremely small distances for precision hair cutting operations. There is also a need for a tool usable in the blade adjustment process which is capable of readily tightening a threaded fastener, and generating a significant amount of torque for tightening the fasteners between the blades to maintain the desired spacing during operation.